Correct Answer - Option 1 : Varied texture
Concepts:
Roofing tiles, Mangalore Pattern, shall be of two classes, namely Class AA and Class A as per IS 654:1962.
Characteristics of Good roof tile are (as per IS 654:1962):
1. Roof tile must act as thermal barrier so that heat due to sun light cannot penetrate inside the room.
2. Roof tile must have less water absorption in order to increase its durability and strength. If moisture penetration is too high, tile may crack. Further, as per BIS 654:1962, the water absorption for tiles of class A shall be less than 20 % and for Class AA shall be less than 18 %.
3. The roofing tile shall be free from impurities like particles of stone, lime or other foreign materials visible to the naked eye either on the surface or on the fractured face of the tile obtained by breaking the tile. However, occasionally, particles up to 2 mm in size may be permissible.
4. When struck, the tile shall give a characteristic ringing sound and when broken the fracture shall be clean and sharp at the edges.
5. Roofing tiles should have high durability, high strength and resistance against dampness.
Note:
Clay roof tiles are extremely popular and they are commonly used because they look good and provide strong resistant against atmosphere and dampness Having an absorption rate of only 6% means they take in less water than their concrete counterparts and are able to remain lightweight.
